Amazon, US Postal Service will deliver on Sundays

Amazon says it is teaming up with the U.S. Postal Service to deliver packages on Sundays.

The Seattle company says Sunday delivery will be available to customers in the New York and Los Angeles metropolitan areas at first. Amazon and the Postal Service plan to roll out service to "a large portion of the U.S. population" next year, including Dallas, Houston, New Orleans, and Phoenix.

Amazon expects Sunday delivery to be popular with members of its Prime service, which costs $79 a year and comes with free two-day shipping on many items on the site as well as access to Amazon's TV and movie streaming service. But Sunday delivery will be available to all Amazon customers.

Shares of Amazon climbed $1.69 to $52 in morning trading.